In the present study, we evaluated the effects of neonatal CPF exposure on behaviors in adulthood that are well established in animal models of depression to reflect 5HT synaptic dysfunction (Cairncross 1984; Cryan et al. 1999; Harkin et al. 1999; Jesberger and Richardson 1985; Kelly et al. 1997; Leonard and Tuite 1981; Richardson 1991; Slotkin et al. 1999). The gene discussed is HTR5A; the disease is major depressive disorder.